The setting is certainly nice: a five-star golf resort high in the Tortolita mountains outside Tucson, Arizona. Despite being in the middle of the desert, water is all around: two golf courses, three pools, a water park, plus three outdoor lawns raked by sprinklers. Inside, conventioneers are unloading displays of surgical instruments, orthopaedic furniture and clear plastic canisters designed to store human fat.

I've come to the Congress on Aesthetic Vaginal Surgery because I want to learn more about one of the fastest growing cosmetic procedures in the US. This newish industry consists of doctors and their clients (clients, not patients, because these surgeries are cash-only elective procedures) who believe the female nether area can be improved upon or remediated. Procedures offered include labiaplasty (trimming or completely removing labia), vaginal rejuvenation (tightening), hymenoplasty ("revirgination") and clitoral "unhooding" – among others.

On my way to check out the exhibits, I pass a 4ft welcome poster of a woman's bare back and well rounded buttocks. At a cosmetic gynaecology conference at a luxury hotel in Las Vegas only six weeks earlier (yes, these surgeries are so popular there are two competing conferences), even the ads for post-surgical "compression garments" were made to look a little S&M sexy, while the mostly male doctors walked around with name badges festooned with identifying ribbons ("Presenter"! "Faculty"! "Attendee"!), looking like generals returning from battle with a chest full of medals.

As I browse, a surgical equipment salesman mistakes me for a doctor and eagerly tries to sell me his new radiostatic scalpel ("Less thermal collateral damage!"), demonstrating its precision by cutting slices out of a piece of raw steak.

Designer vagina surgery is big business: according to the American Society for Aesthetic Plastic Surgery, in 2009 female consumers spent an estimated $6.8m (£4.4m) on these procedures (the figure counts only plastic surgeons, not gynaecologists). Its popularity is rising in the UK, too – in 2008, the NHS carried out 1,118 labiaplasty operations, an increase of 70% on the previous year. And figures released this year show that plastic surgery company the Harley Medical Group received more than 5,000 inquiries about cosmetic gynaecology in 2010, 65% of them for labial reduction, the rest for tightening and reshaping.

The only reason I know about cosmetic vaginal surgery is that, while researching my latest book, I was given temporary faculty status at the medical school of the university where I teach creative writing, so I could observe obstetrics and gynaecology students. Somehow, I began to get spam emails addressed to "Dr Lee", extolling the "revenue expanding" virtues of learning vaginal rejuvenation. And it's clear at this conference that the bulk of participants are indeed not plastic surgeons but run-of-the-mill obstetricians and gynaecologists who see this as their passport out of traditional practice.

When I ask these doctors about the drastic switch from delivering babies to doing cash-only cosmetic surgeries, many seem uncomfortable. A few sheepishly say they are just exploring their options. The ones already practising cite the rising costs of malpractice insurance, dwindling insurance and government reimbursements (in the US healthcare model, nine months of prenatal care and a normal vaginal delivery nets these primary care providers less than $2,000 [£1,288]). Others talk of a desire for more control over their schedule, rationalising the switch as a "family values" move.

But the irrefutable fact of the matter is that these cosmetic procedures can make you rich. As one speaker makes a presentation about his successful cosmetic-gyn practice, the wallpaper from his laptop appears on screen: various shots of him with his Porsche. The message is simple. A straightforward labiaplasty, done in-office, in a few hours, nets about $5,000 (£3,222). Enough customers and you, too, can live the good life.

My late father was an anaesthetist and I occasionally attended conferences with him. While they took place in similarly junkety locations, these were staid affairs: endless seminars on the newest paralytic and narcotic agents, endless charts of rates of metabolisation of these drugs. Here, there is a distinct buzz of excitement as one might find at, say, a seminar on get-rich-quick investing. And, in fact, that's much what this is: doctors are encouraged to think of themselves not only as healthcare providers, but as individual economic actors competing in the free market. In what feels almost like a mini-MBA programme, we sit through presentations on search engine optimisation (SEO), burnishing one's online reputation and marketing.

Practitioners trade ideas on how to increase revenue by cutting costs; finding ways to do procedures using local anaesthesia, for instance, in order to avoid the expense of having to rent an operating room at a hospital and pay an anaesthetist. In surgery, assistants are needed to hold retractors, instruments that keep the incision open; one enterprising doctor displays a special clamp he has invented, patented and will be selling: a U-shaped gizmo that will make surgical assistants unnecessary.

On a larger level, the more activist doctors here are also waging a kind of internecine war, determined to keep cosmetic-gyn within their purview, lamenting how they let the breast implants business "get away" from them and become the sole province of plastic surgeons.

Some here are presenting "how-to" videos on their methods to beautify the labia, arguing with other presenters about whether the "wedge" or "rim" technique is better; cautioning attendees not to pull the sutures too tight, so as to produce "scalloped" edges. And the body, as it heals, always has its surprises: "I get the lumpy-bumpies just like anyone else," admits one, showing his solution of shaving off bead-like skin tags that form around an incision, much in the way your grandmother might de-pill a sweater.

Since many of the obstetricians and gynaecologists at the conference are untrained in plastic surgery, one big question begins to bother me: on what/whom they will practise?

The answer is, they don't – or, often, not much. A number of those here plan to watch the videos and start operating. Indeed, in one session, a doctor asks how to overcome beginner's nerves – and what are your obligations to let your patient know? "Do it on a 60-year old – it won't matter!" comes one helpful suggestion from the audience.

Sherie, a 36-year-old from Oregon, spent $18,000 (£11,600) on vaginal surgery last year. "In my mid-20s, I noticed that my inner labia were larger than my outer labia," she tells me, "but at that point I wasn't overly concerned by it. Then I had laser hair removal for my bikini line and realised that not everyone might be like me. I browsed through one of my brother's Playboys to see what the girls looked like. Some seemed to have very small or almost no labia. It was around that time that I began to wish mine were smaller, but I still had no intention of doing anything about it."

When Sherie got a job selling medical devices to gynaecologists, she became aware that some doctors were performing vaginal rejuvenation, but still thought that it was "a pretty extreme step". Then she had three children in three years. "It seemed that all I did was work, have babies and take care of them."

Although she tells me that her husband never had any issues with how her vagina looked, it was around that time that she started to think "about the improvements that I wanted to make after the tolls of childbirth". She contacted a plastic surgeon she knew and trusted, and arranged to have the labiaplasty in his office. "I was shocked when he handed me the mirror after he was done," she remembers, "because the cuts and stitches were going the complete opposite way from how I had thought they would, and I didn't see how I would heal looking better and without very obvious scars. I went into freak-out mode and couldn't believe what I had done." She went back to work for 10 hours and by the end of the day was in "excruciating pain".

Rather than waiting for her botched surgery to heal, Sherie decided to get it corrected straight away. After talking to other doctors and surgeons, she phoned a Dr Red Alinsod. "We talked about not only labial reduction but other possible procedures I might want to get done since I was going to endure some pain and downtime anyway. This made sense to me – to just get any and all done down there while I had the chance. I'd had heavy bleeding since having children and a haemorrhoid but, after looking at Dr Alinsod's website, I started to think about vaginal tightening, too. I thought, well, after three kids it can't hurt."

Together, they decided on an ablation (for the bleeding), haemorrhoidectomy, labia reduction, hood reduction (to match her new labia), vaginal tightening and repair of her perineum. "The next few weeks and months were a little painful at times, but it all healed beautifully," she says. "Not a day has gone by that I have regretted having this done, and I would encourage anyone [who is] unhappy to consider looking into it, as long as you go to the right surgeon and are willing to spend what it takes to get the best results."

Sherie seemed thrilled by the speed with which Alinsod responded to her initial inquiry and how accommodating he had proved to be: "He talked on the phone for 45 minutes," she says of their pre-operative conversation, "and even extended his normal working day to perform my surgery."

When it comes to elective medical procedures, customer service is, of course, part of the package but I spend a lot of time with Alinsod over the course of the conference (he is its organiser) and he also appears to be a skilful surgeon with an unapologetic passion for what he does. Indeed, the atmosphere is almost festive with delegates' enthusiasm to come up with new forms of cosmetic gynaecology, and new ways to encourage women to have it. One doctor's sales pitch invites clients to "get double-D labia to go with those double-D implants!"

I am unsure of what attractive vaginas are supposed to look like, but after a few presentations with their before-and-afters, a clear surgical ideal emerges: labia inflated to banana-like pontoon proportions, a look that I can only describe as pure, mammalian oestrus. The aesthetic ideal goes one step further when Alinsod, who practises in body-conscious southern California, tells us that his most popular labiaplasty procedure is one he invented, a "smooth" look, called the Barbie (after the doll), that involves shearing off the entire labia minora, the inner lips, to leave a "clamshell" look.

This constant casual talk about vaginas, with the slightly ribald asides about sexual function, feels like a continuation of the trickle-up of the porn aesthetic that started about 10 years ago, when the Brazilian wax went mainstream. (On recently observing a birth as part of my research, I mentioned to one of the nurses that I thought pre-delivery shaving of the genital area wasn't done any more. She looked at me as if I were 100 years old and said, "Honey, they all come in this way!")

It was not the porn aesthetic that motivated Ella, a 48-year-old nurse from Texas, to have her surgery, however, but a growing dislike of the way she looked, combined with increasing discomfort during sex. Like Sherie, she had to go back for corrective surgery after her initial operation did not go as planned. "After I had my children, my labia became longer, less full and discoloured" she says. "During sexual intercourse, I would always have to move my labia out of the way to keep them from being pulled into my vagina. But they inevitably would get pulled and have small tears on the skin as a result. I was an avid cyclist and it became painful to ride. I spoke with my regular gynaecologist and he told me that they offered labial reduction at the army facility in San Antonio – my husband was on active duty – so, in 2006, due to the cost involved, I opted to have it there. At first, I was happy, but when I continued to have problems with my perineum, I contacted Dr Hailparn. Since I was going to be undergoing vaginal rejuvenation, I decided to have her fix my labia, too. I no longer have any difficulty with intercourse or any pain while cycling. The symmetry is beautiful and I now have a more aesthetically pleasing labia." She says her husband thinks the surgery was worthwhile, "because it has enhanced our sexual intimacy".

It should be noted that labiaplasties done for purely functional reasons, such as dyspareunia (pain during sex), may be categorised as medically necessary and therefore eligible to be covered by insurance. However, when I spoke to practitioners at the conference, they waved away the idea that either they or the client would want to take that route. "It'll take me 10 minutes, but I'll get only $300," one explained. "And it'll look like I spent 10 minutes on it." Another agreed, explaining that much of the elective fee he charged had to do with the two hours he'd spend "making it look pretty".

One female gynaecologist says she does these procedures in part because she empathises with her patients, and emphasises the functional as well as the cosmetic aspects. She tells me about the discomfort she has experienced from her own "misshapen labia" and says the reason she hasn't had surgery is simply because she has yet to find the right doctor.

There are few female surgeons at the conference in Tucson, and between the endless pictures of labia and the macho patter ("I took her from a four-finger vagina to a two-finger, and boy was her husband happy" – complete with a demonstration, via gloved digits), it is invariably awkward reporting it as a female journalist. Alinsod has been generous in granting me full access, but the others here are quite wary as to how their field might be portrayed. Indeed, a good portion of the seminars are devoted to how to counter criticism both from feminists accusing "disease mongering" doctors of preying upon women's insecurities to create a demand for procedures that they didn't need, and from negative press in more mainstream media, such as the story that ran in Cosmopolitan magazine last year headlined "VAGINAS UNDER ATTACK: Don't Let Your Greedy Gyno Talk You Into This Horrible Mistake".

That evening, during pre-dinner drinks, I try to take advantage of the more casual atmosphere to canvass the doctors: did they really expect to go home and start doing the surgeries after just watching a few videos? Apparently, one can take a training course from a more established doctor, but as with everything in this for-profit business, that comes at a price. Some grumble about "tuition fees". Studying for a few weeks with the surgeon who's been on Doctor 90210, for instance, apparently costs $75,000 (£48,339), so many cost-conscious doctors prefer to skip this step.

I must look incredulous, because another doctor assures me that one always has the option to buy an additional "cadaver lab" workshop in which to practise. "Do they hold the cadaver labs at fancy golf resorts like this one?" I joke, imagining the Ritz trying discreetly to wheel in covered gurneys with the fresh flowers.

But nobody laughs because apparently they do sometimes conduct cadaver labs at luxury convention hotels (though not at this particular conference), and some are very touchy about the doctor stereotype that they like to play golf. The most offended doctor – whose "pick-and-mix" presentation is all about how to persuade a patient to add a cosmetic-gyn procedure to an incontinence surgery in which Gore-Tex mesh is implanted as a kind of sling to hold up the organs (a procedure currently being questioned by the Food and Drug Administration for severe side-effects and frequent failure) – tells me to get lost and drags his colleagues away.

When it's time to take our places at dinner, I'm still doing an interview and by the time I'm done, almost all the seats are taken, but I happen to spy an opening fortuitously next to one of the few women attendees. I start sliding into the seat, only to be elbowed out by Dr Pick and Mix.

"I was about to sit there," I say, slightly shocked.

"I'm going to sit with my friends," he sneers, sitting down and laying his arm possessively on the back of the attractive young woman's chair. By then, all the tables have filled up. I feel like the odd person out in a game of musical chairs, and no one seems inclined to make room for me. The medics have, in general, been cordial – some are excited about the publicity – but I begin to wonder if I'll be eating alone in my room tonight.

Then, at the last minute, a friendly middle-aged doctor waves me in. It turns out he's part of the larger aesthetic surgery convention going on at the hotel and is just sitting in on the cosmetic-gyn dinner before his main business tomorrow: conducting workshops on Botox and dermal filler.

I had noticed, on a different floor, tantalising glimpses of doctors and nurses in scrubs, and patients with bloodied bandages on their faces, staggering from meeting rooms with names such as the Wild Burro Boardroom. Yet every time I'd tried to peek in, a security person had shooed me away. From the sign on one door, the doctors inside had been practising something called the Silhouette facelift, in which the skin is lifted by threading sutures under it and pulling them tight.

I tell my dinner companion that I'm fascinated by how doctors learn to do these procedures that are not taught in medical school, and ask if I can observe his Juvéderm workshop, never dreaming he'll say, "Sure, why not?"

When I enter the room the next day, a security guard jumps on me: "You have to leave now!" and puts a hand up to my arm to escort me out. We argue until Dr Facial Filler, absorbed mid-procedure, looks up and tells the guy I'm OK.

It takes a moment to get used to the sight of a fully-clothed woman lying on a tablecloth on a banquet table, as if at a magic show. The group is half a dozen doctors and their nurses from a single medical practice who have paid a hefty fee to learn how to do Juvéderm, a facial hyaluronic acid filler that plumps up lips and smoothes wrinkles. First, they practise the local anaesthetic injections – on each other.

"Oops! Sorry!"

"A little higher, angle it in a little – that's it."

"Oh, Lord, don't kill me."

There is a lot of laughing, maybe a little exaggerated awkwardness. Dr Facial Filler then demonstrates how to inject the filler on the lips of one of the female doctors. "Great, 'cause I've got a date tonight," she says, patiently lying on the hard table as he pokes a needle into the back of her upper lip. His task is to transfer an entire syringe of semi-viscous content into a space that's already filled with tissue and fat. He has to push down hard on the plunger, and the process is slow. The doctor-patient now has an enormous, misshapen upper lip. "Normal, perfectly normal," Dr Facial Filler says, kneading vigorously, trying to get some of the filler to travel to the less inflated side. At one point he's using two hands, as if he's rolling out pasta. When he finishes, her face is still lopsided and slightly bruised.

It's even more awkward when the doctors try their hand, the male doctors working on the female doctors or the nurses. The atmosphere is like a children's art project. But with needles. And blood. Because skin is being breached (the needle they use for the anaesthesia is particularly large), there is bleeding, but Dr Facial Filler gleefully chucks the soiled gauzes in the waste basket, declaring, "If it's not dripping, it's technically not medical waste!" By the end of the workshop, out walk half a dozen ducks waiting to turn into swans, ready for lunch.

Sunday evening, the conference comes to an end. Laid on a table are a bunch of framed, official-looking certificates made on the organiser's computer, certifying that doctors have physically been here for the presentations. I'm still haunted by the idea that some are going to go home, hang them on the wall and begin cutting. Perhaps in recognition of this, one of the last sessions is on the new-new market: "revision surgery".

At the earlier conference in Las Vegas, I had seen a similar presentation: in one slide, showing 150cc of human fat (looking like orange juice in a pitcher), doctors had to puzzle out what to do about a too-enthusiastic liposuction of the thigh area near the vagina, which had resulted in a widening of the opening so severe that the client's tampons were falling out. Here in Tucson, a PowerPoint slide is labelled "Labiaplasty Disasters" and what I see resembles crushed vegetables more than female genitalia.

A common problem, I learn, is when doctors don't take into consideration that labia can retract, which can turn a simple trimming job into an inadvertent Barbie. Luckily, Alinsod, the inventor of the Barbie, has also come up with a reparation surgery: flaps of skin grafted to create the trompe l'oeil of resurrected labia. I'm impressed by the man's constant inventiveness. He also clearly enjoys what he does ("I could do labiaplasties all day!") and has satisfied patients, judging from his busy practice – so why do I feel a continuing sense of unease?

Alinsod, in fact, is responsibly working toward using conferences such as this to help set professional standards that will perhaps assist in fostering the legitimacy of cosmetic gynaecology and lead to safety standards and clinical trials. Indeed, in an unpoliced medico-industry, without the doctors organising themselves and sharing their data, safety questions and adverse effects might go unaddressed (what impact these procedures might have on childbirth, for instance, is still unknown).

I realise that my disquiet is not so much to do with individual doctors but whether, in an age in which a good portion of Americans are uninsured and don't have access to healthcare, this is the best use of limited medical resources. In an odd coincidence, at the same time as the Congress on Aesthetic Vaginal Surgery was taking place, new legislation was being enacted in Arizona that cut off state funding for organ and bone marrow transplants – life-saving but costly procedures that were being denied in the name of necessary healthcare rationing.

Yet doctors have to make a living, too, and many at the conference felt almost victimised by massive medical school debt and a changing healthcare environment that they believed was "forcing" them into aesthetic vaginal surgery and other cash businesses.

As Dr Porsche and the other most tightly scheduled doctors run to catch planes back to their busy practices, a handful linger. Everybody's been so immersed in the all-day presentations that they've hardly ventured beyond the meeting rooms, but now they drift on to the hotel porch. As the Tortolita mountains redden in the dusk, they put their feet up by the outdoor chimney, shed their name badges and order drinks made with expensive, artisanal tequilas. In the desert all around are the lush golf courses and artificial pools squandering a finite, life-giving commodity, offering a kind of gleeful profligacy to those willing to pay.